Enrichment of microbial communities tolerant to the ionic liquids tetrabutylphosphonium chloride and tributylethylphosphonium diethylphosphate.

The aims of this study were to identify thermophilic microbial communities that degrade green waste in the presence of the ionic liquids (IL) tetrabutylphosphonium chloride and tributylethylphosphonium diethylphosphate and examine preservation methods for IL-tolerant communities. High-solids incubations with stepwise increases in IL concentration were conducted to enrich for thermophilic IL-tolerant communities that decomposed green waste. 16S rRNA sequencing of enriched communities revealed microorganisms capable of tolerating high levels of IL. Cryogenic preservation of enriched communities reduced the IL tolerance of the community and decreased the relative abundance of IL-tolerant organisms. The use of cryoprotectants did not have an effect on microbial activity on green waste of the stored community. A successful approach was developed to enrich communities that decompose green waste in thermophilic high-solids environments in the presence of IL. Alternative community storage and revival methods are necessary for maintenance and recovery of IL-tolerant communities. The enriched communities provide a targeted source of enzymes for the bioconversion of IL-pretreated green waste for conversion to biofuels.

Optimized Dosing and Delivery of Bacteriophage Therapy for Wound Infections.

Lytic bacteriophages, viruses that lyse (kill) bacteria, hold great promise for treating infections, including wound infections caused by antimicrobial-resistant Pseudomonas aeruginosa. However, the optimal dosing and delivery strategies for phage therapy remain unclear. In a mouse wound infection model, we investigated the impact of dose, frequency, and administration route on the efficacy of phage therapy. We find that topical but not intravenous delivery is effective in this model. High-doses of phage reduces bacterial burden more effectively than low-doses, and repeated dosing achieves the highest eradication rates. Building on these insights, we developed "HydroPhage", a hyaluronan-based hydrogel system that uses dynamic covalent crosslinking to deliver high-titre phages over one week. HydroPhage eradicates infections five times more effectively than intravenous injection. We conclude that hydrogel-based sustained phage delivery enhances the efficacy of phage therapy and offers a practical, well-tolerated option for topical application.